Introduction: Cross-sectional studies show an association between obesity and earlier timing of puberty. However, few studies have considered how the tempo of puberty potentially impacts upon weight and adiposity. This study assessed longitudinal associations for pubertal timing and tempo to weight-related outcomes in adolescents.
Methods: 226 healthy adolescents (46% female; 10-13y at recruitment) from the ARCHER cohort study1 of puberty hormones were followed over a 3-year period. Annual anthropometric and body composition (via bio-electrical impedance) measures were analysed against pubertal timing (earlier/later) and tempo (fast/slower) groups derived from non-linear growth curve modelling of annual self-reported Tanner stage.
Results: Earlier pubertal timing was significantly associated with higher absolute levels of adiposity (including weight, BMI z-score, waist circumference, waist-to-height ratio and fat mass) in girls, and more rapid increases in adiposity (including weight, BMI z-score and fat mass) over 3 years among boys (all p<0.05). Faster pubertal tempo predicted more rapid increases in weight and BMI z-score over 3 years among girls (both p<0.05), but paradoxically, less rapid increases in central adiposity (including waist circumference and waist-to-height ratio; both p<0.01) among boys. Adjustment for baseline BMI z-score attenuated the pubertal timing associations observed in girls, but other results remained largely unchanged.
Conclusions: Pubertal timing and tempo showed sex-specific relationships to weight-related outcomes. This study identified pubertal tempo as a potentially relevant risk factor for weight and central adiposity in girls and boys, respectively. Findings for pubertal timing align with the cross-sectional evidence. However, our results in girls showed a stronger association for pubertal timing to pre-existing adiposity than weight gain during adolescence. The reverse was apparent in boys. These associations may assist in early identification of adolescents at risk of excess weight gain during adolescence. Findings also highlight the importance of sex- and developmentally-appropriate weight management advice/strategies for youth.